English: Cryo-electron tomography analysis of frozen-hydrated Synechococcus cell lamella
Tomographic slices (a, c) and segmented volumes (b, d) of cyanobacteria cells grown under high light (HL) (a, b) and these HL-grown cells transferred to low light (LL) condition for 1−2 days (c, d). Tomographic slices at high magnification (e, g, i) and segmented volumes (f, h, j) of cyanobacteria cells grown under HL. Outer and plasma membranes are in blue, thylakoid membranes in gold, glycogen granules in cyan, carboxysomes (“C”) in green, and large dense granules (“G”) in pink, most likely the polyphosphate bodies. Yellow arrows point to the gaps between two thylakoid membrane edges for the emergence of newly synthesized thylakoid membrane rafts. The red arrow points to the thylakoid tip located in the vicinity of the plasma membrane, but not connecting to it. The white arrow points to the tubular structures. Scale bars, 200 nm in panels (a, c), 100 nm in panels (e, g, I). Single slice images have a thickness of 2.49 nm and the tomographic slices images are constructed from superimposed serial slices with the same thickness. Representative Cryo-ET images were derived from at least three biologically independent preparations with similar results.